Author(s): Islam, MR (Islam, Md Rasidul); Mojumder, MRH (Mojumder, Md Rayid Hasan); Moghal, BK (Moghal, Biazid Kabir); Islam, ASMJ (Islam, A. S. M. Jannatul); Miah, MR (Miah, Mohammad Raza); Roy, S (Roy, Sourav); Kumar, A (Kumar, Anuj); Shihavuddin, ASM (Shihavuddin, A. S. M.); Ashique, RH (Ashique, Ratil H.)

Source: PHYSICA SCRIPTA Volume: 97 Issue: 4 Article Number: 045806 DOI: 10.1088/1402-4896/ac57e0 Published: APR 1 2022

Abstract: Here, we provide a systematic assessment of biaxial strain effects on the electronic, phonon, and optical properties of monolayer transition metal dichalcogenides (TMDs) XTe2 (X = Mo and W) using density functional theory calculations. We observed a large direct bandgap of 1.163 eV and 0.974 eV for MoTe2 and WTe2, which reduced to 1.042 eV and 0.824 eV in the spin-orbit coupling ambient. The XTe2 structures show a tunable bandgap with the variation of the applied biaxial strains. Due to the breaking of inversion symmetry, a large spin-valley coupling emerged at the valance band edges for both MoTe2 and WTe2 monolayers under applied biaxial strain. The phonon properties with different biaxial strains reveal that monolayer MoTe2 is more stable than the WTe2 structure. The calculated optical properties demonstrate that the dielectric constant and absorption coefficient of MoTe2 and WTe2 move to higher photon frequencies when the compressive strain is increased. On the other hand, with the increase in tensile strain, a red-shift behavior is found in the calculated optical properties, indicating the suitability of the XTe2 monolayer for different infrared and visible light optical applications.

Accession Number: WOS:000765546000001

Author Identifiers:

Author Web of Science ResearcherID ORCID Number

Roy, Sourav 0000-0001-5739-2525

ISSN: 0031-8949

eISSN: 1402-4896

Full Text: https://iopscience.iop.org/article/10.1088/1402-4896/ac57e0